New Tiny ETW WHIPPET Engine?

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Richard-Vanderpol

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There are a lot of lovely parts with this engine:

 
I like small engines, all small engines, no matter how simple, and I don't care where and by whom.....
But, This is the forum " Home model engine "
If you want to advertise : Please consult the admin !
Correct, I was given the engine by Enjomor/StirlingKit. I have then homemade the parts around it.

I'm very happy though if it is removed from here.
 
this design is not helped by the top outlet being angled down -

No problem with a bit angled outled pipe from engine, its length of the hose from the top of the angled pipe on the engine to the top of the pipe on the cooland barrel/radiator must be long enough to keep coolant circulating.
 
No problem with a bit angled outled pipe from engine, its length of the hose from the top of the angled pipe on the engine to the top of the pipe on the cooland barrel/radiator must be long enough to keep coolant circulating.
Thanks, I will drop the lower point on the tank, then raise it further on the stand and increase the upper point. That should give a longer upper pipe run.
 
Using the latest CAD I think then I can go from this:

whippet-coolant-pipes-01.jpg


to this

whippet-coolant-pipes-02.jpg
 
Yes, a bit higher to top to increase stream of hot coolant from the engine. Water is heated, it gains kinetic energy from the heating source and becomes excited. As a result, the water becomes less dense, expands, and thus rises. The warmer fluid will "float" above the cooler fluid, and the cooler fluid will "sink" below the warmer fluid. This phenomenon of natural convection is known by the saying: "heat rises". Convection moves the heated liquid upwards in the system as it is simultaneously replaced by cooler liquid returning by gravity. A good thermosiphon has very little hydraulic resistance so that liquid can flow easily under the relatively low pressure produced by natural convection.
 
whippet-coolant-pipes-03.jpg


A bit of a mess, but I wanted to modify the connection points and test it out. The result is the water now gets quite hot and you can feel the gradient top to bottom of the tank. Cool and thanks to @Mechanicboy

You can feel the temperature difference on the upper and lower plastic tubes, so there is water thermally cycling around the system.

The plastic lid has a ~8mm diameter hole in it, there just to stop water going everywhere.
 
The angle of the bottom hose looks OK, but the top hose just doesn't look right. Should it run "downhill"? If I had the engine, and knew what I was doing, I would machine off the outlet from the head and somehow make a new outlet that pointed up to the top pipe in the hopper. My car has a thermosyphon system and they can work OK.
 

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